Apparatus for cleaning substrate and method for cleaning substrate

Abstract

Provided is an apparatus for cleaning a substrate. The apparatus includes a stage on which a substrate is loaded, a cleaning liquid supply unit supplying a cleaning liquid to the substrate, an oscillator transmitting sound waves to the substrate for cleaning the substrate, and at least two piezoelectric members disposed on an end portion of the oscillator at a predetermined distance apart from each other so as to generate the sound waves.

1. An apparatus for cleaning a substrate, comprising:
 a stage on which a substrate is loaded; 
 a cleaning liquid supply unit supplying a cleaning liquid to the substrate; 
 an oscillator transmitting sound waves to the substrate for cleaning the substrate; and 
 at least two piezoelectric members disposed on an end portion of the oscillator at a predetermined distance apart from each other so as to generate the sound waves, wherein the at least two piezoelectric members comprise a first piezoelectric member and a second piezoelectric of different thicknesses. 
 
     
     
       2. The apparatus of  claim 1 , further comprising:
 electrodes facing each other with the piezoelectric members being disposed between the electrodes; and 
 a vibration generator in which the piezoelectric members and the electrodes are disposed, the vibration generator being coupled to the end portion of the oscillator. 
 
     
     
       3. The apparatus of  claim 1 , further comprising:
 first electrodes facing each other with the first piezoelectric member being disposed between the first electrodes; 
 second electrodes facing each other with the second piezoelectric member being disposed between the second electrodes; and 
 a vibration generator in which the first and second piezoelectric members and the first and second electrodes are disposed, the vibration generator being coupled to the end portion of the oscillator. 
 
     
     
       4. The apparatus of  claim 1 , wherein the first and second piezoelectric members have the same shape. 
     
     
       5. The apparatus of  claim 1 , wherein the oscillator is shaped like a rod, and the first and second piezoelectric members are symmetrically disposed with respect to an imaginary line passing through a center of the oscillator and parallel with a length direction of the oscillator. 
     
     
       6. The apparatus of  claim 5 , wherein the first and second piezoelectric members and the imaginary line are adjusted at predetermined angles from each other according to a length of the oscillator. 
     
     
       7. The apparatus of  claim 1 , wherein the oscillator is shaped like a rod, and the first and second piezoelectric members are asymmetrically disposed with respect to an imaginary line passing through a center of the oscillator and parallel with a length direction of the oscillator. 
     
     
       8. The apparatus of  claim 1 , wherein the stage is a chuck configured to fix the substrate utilizing a vaccum force or an electric force and is connected to a motor for rotating the chuck. 
     
     
       9. The apparatus of  claim 1 , wherein the cleaning liquid is selected from the group consisting of deionized water, aqueous ammonia, hydrogen peroxide, hydrofluoric acid, ammonium fluoride, phosphoric acid, and mixtures thereof. 
     
     
       10. The apparatus of  claim 1 , wherein the oscillator is inclined at an angle from the substrate. 
     
     
       11. The apparatus of  claim 1 , wherein the oscillator is parallel or perpendicular to the substrate. 
     
     
       12. The apparatus of  claim 1 , wherein the at least two piezoelectric members generate the sound waves, respectively, and the sound waves interfere constructively with each other at a surface of the oscillator adjacent to the substrate.